Glass-ionomer cements represent a new type of dental materials widely clinically applied owing to their good adhesion to dental tissue, caries-protective effects, biocompatibility and simple handling. They are two-component materials commercially available in forms of powder or liquid. The two components are mixed manually or automatically in a vibrator to produce a compact mixture. In addition to chemical, light-polymerizing hybrid glass-ionomer cements are also available. A description is given of physical and chemical features of these materials, their classification and use in particular clinical cases.